lsp-treemacs-call-hierarchy times out for Python with basedpyright.

[alamaison]

I'm using Emacs 30.1, the latest lsp-mode and lsp-treemacs from MELPA and the latest basedpyright as the LSP server implementation. When I call M-x lsp-treemacs-call-hierarchy with the cursor on a function definition, I eventually get the message helm-M-x-execute-command: Timeout while waiting for response. Method: textDocument/prepareCallHierarchy. But in the log I can see that prepareCallHierarchy returned quickly:

[Trace - 12:58:26 PM] Sending request 'textDocument/prepareCallHierarchy - (126)'.
Params: {
  "textDocument": {
    "uri": "file:///home/alex/path/to/my/file.py"
  },
  "position": {
    "line": 60,
    "character": 22
  }
}


[Trace - 12:58:26 PM] Received response 'textDocument/prepareCallHierarchy - (126)' in 2ms.
Result: [
  {
    "name": "run_document_download",
    "kind": 12,
    "uri": "file:///home/alex/path/to/my/file.py",
    "range": {
      "start": {
        "line": 60,
        "character": 10
      },
      "end": {
        "line": 60,
        "character": 31
      }
    },
    "selectionRange": {
      "start": {
        "line": 60,
        "character": 10
      },
      "end": {
        "line": 60,
        "character": 31
      }
    }
  }
]

If I call (lsp-request "textDocument/prepareCallHierarchy" (lsp--text-document-position-params)) directly I get the following traceback:

Debugger entered--Lisp error: (error "Timeout while waiting for response.  Method: textDocument/prepareCallHierarchy")
  signal(error ("Timeout while waiting for response.  Method: textDocument/prepareCallHierarchy"))
  error("Timeout while waiting for response.  Method: %s" "textDocument/prepareCallHierarchy")
  lsp-request("textDocument/prepareCallHierarchy" (:textDocument (:uri "file:///home/alex/path/to/my/file.py") :position (:line 60 :character 26)))
  eval((lsp-request "textDocument/prepareCallHierarchy" (lsp--text-document-position-params)) t)
  #f(compiled-function () #<bytecode 0x40becfeaac1167f>)()
  #f(compiled-function () #<bytecode -0x5db3e1955cb81d1>)()
  handler-bind-1(#f(compiled-function () #<bytecode -0x5db3e1955cb81d1>) (error) eval-expression--debug)
  eval-expression((lsp-request "textDocument/prepareCallHierarchy" (lsp--text-document-position-params)) nil nil 127)
  funcall-interactively(eval-expression (lsp-request "textDocument/prepareCallHierarchy" (lsp--text-document-position-params)) nil nil 127)
  call-interactively(eval-expression nil nil)
  command-execute(eval-expression)

I'm not sure how to start debugging further than this. Any idea what the problem is?